JPS63231132A - Defrosting control of variable capacity type airconditioning machine - Google Patents

Abstract

PURPOSE:To prevent the useless consumption of energy and the reduction in indoor temperature, by a method wherein the range of rotating number of a compressor which does not allow defrosting operation is fluctuated in accordance with the change of an atmospheric temperature and the defrosting operation is controlled so as not to be introduced in the range of the rotating number. CONSTITUTION:An atmospheric temperature is shown on a horizontal axis and the rotating number of a compressor is shown on a vertical axis: A wide full line 1 shows a line indicating stable operation of an air-conditioning machine free from frosting of an outdoor heat exchanger. The range of rotating number at which the compressor should be introduced into defrosting operation is shown by the range of hatching lines. The number of rotation at which the compressor should be introduced into defrosting operation is set in accordance with the change of the atmospheric temperature in such a manner. Then, the defrosting operation may be controlled so as not to be introduced when the outdoor heat exchanger is not frosted or the amount of frosting is small. Accordingly, the defrosting operation may be effected only when defrosting is necessitated really and the waste of energy due to useless defrosting operation and the reduction of an indoor temperature due to the same may be prevented.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a defrosting control method for a variable capacity air conditioner, and in particular to a defrosting control method for a variable capacity air conditioner suitable for performing defrosting operation without waste. The present invention relates to a defrosting control method.

[Conventional technology]

In general, air-cooled heat pump nitrogen conditioners use the outdoor heat exchanger VCSA during heating operation, which reduces the heating capacity and requires defrosting operation. This can be said to be a negative factor. Therefore, it is desirable to perform the defrosting operation only when necessary, and not to enter the defrosting operation at least once when there is no interest or when the defrost operation is low.

Traditional exorbitant system? I11 is, for example, Special Publication No. 61-9542.
As described in the above publication, a decrease in the heating power level was detected based on the temperature difference between the indoor temperature and the indoor heat/heater temperature, and it was determined whether or not to enter defrosting operation. However, the compressor electric l1
A variable capacity air conditioner (inverter air conditioner) that controls capacity by changing the rotational speed of the JJ machine.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art described above during defrosting operation and to provide a heat pump type air conditioner that can perform comfortable heating operation.

[Means for solving problems]

The above object is achieved by automatically predicting the start time of the defrosting operation and raising the set temperature for a predetermined period of time before starting the defrosting operation.

[Effect]

By using a configuration that predicts the start time of defrosting operation and performs control to raise the set room temperature before starting defrosting operation, it is possible to achieve high efficiency and comfort without losing the timing when defrosting is originally required. You can get an excellent heat pump type air conditioner.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG. 1 is a block diagram showing the configuration of a room temperature control device for a heat pump type air conditioner. Reference numeral 1 denotes a temperature control circuit for detecting frost formation, which detects, for example, the temperature of an outdoor heat exchanger and the temperature of the outside air. 2 is a defrosting prohibition time timer, which is used to appropriately set the defrosting timing of the heat pump type air conditioner. A defrosting operation determination circuit 3 generates a defrosting operation signal 4 at a timing when defrosting is required. Reference numeral 5 denotes a room temperature detector, which outputs the detection result to the defrosting operation determination circuit 3.

6 is a temperature setting device for setting a set room temperature. 7 is a control and arithmetic circuit, which controls the setting of the defrosting start time, the set room temperature before the start of defrosting operation, and the set room temperature change time;
The air conditioning load in the room is calculated and predicted from the amount of change in the room temperature detector 5, etc., and the compressor 1o,
The defrost valve 11 and the blower 12 are controlled to generate an evaporator (not shown).
Defrost.

The set room temperature change time is stored in the storage device 8. With this configuration, the heat pump type air conditioner of this embodiment can determine the appropriate defrost timing according to the amount of frost on the outdoor heat exchanger based on the defrost operation signal 4 from the defrost operation determination circuit 3. It is possible to control the defrosting operation after setting the defrosting timing in advance.On the other hand, the defrosting timing can be controlled before the defrosting start time and the arithmetic circuit 7 can control the defrosting operation before starting the defrosting operation. The set room temperature set in the temperature setting device 6 is increased by a predetermined temperature only during the set room temperature change time.

FIG. 2 shows a control flow diagram of the control and arithmetic circuit 7 shown in FIG. If there is a defrosting operation signal, the remaining defrosting prohibition time 1 and the set room temperature change time are judged to be large or small. If the remaining defrost prohibition time 1 is longer than the set temperature change time τ, the heating operation continues, but if it is shorter than the set temperature change time τ, the room temperature drop temperature ΔT and The set temperature is corrected based on the room temperature decrease temperature C at the end of defrosting with respect to the set room temperature A.

Here, if the remaining defrost prohibition time 1 is 0, the heating operation is maintained as it is, but if the remaining defrost prohibition time 1 is O and there is a defrost signal, the defrost operation is performed. Regarding the set room temperature change time τ, the time required for the heating capacity of the air conditioner to rise to the set room temperature - is stored as an initial table. The set room temperature change time τ required for the next operation is corrected each time. This enables comfortable heating operation.

FIG. 3 is a room temperature change diagram according to an embodiment of the present invention, in which the set room temperature is increased by a temperature difference t during the set room temperature change time τ before the start of defrosting operation with respect to the set room temperature A set by the user. By setting the room temperature to the set room temperature B, the room temperature changes as shown by the solid line in the figure, and even if the heating capacity in the defrosting operation decreases, the room temperature at the end of defrosting changes as shown by the conventional broken line. , the temperature difference with respect to the set room temperature A can be reduced from D to C, and the discomfort that the user has conventionally felt due to cold can be eliminated and comfort can be improved. Furthermore, according to this embodiment, by performing the heating operation without changing the defrosting operation timing, the state with a large amount of frost formation, that is, the efficiency,
Since there is no need to extend the heating operation state with low capacity, the set room temperature change time τ can be shortened, the efficiency of the heating operation can be increased, and defrosting can be reliably performed.

In this example, when the temperature difference and the set room temperature change time become small (step (8)), the rotation speed of the compressor @ becomes the minimum rotation speed I 50 Orpm, and if the heating load does not change rapidly, , the rotation speed of the compressor decompresses near +50 Qrpm.

Now, when the outside air temperature becomes low and the outdoor heat exchanger starts to have a box, the heating capacity will decrease, so the rotation speed of the compressor is increased and the rotation speed of the pressure MM@ is increased so that the heating capacity is above a certain value. changes. Furthermore, the number of outdoor heat exchanger boxes increased, the rotation speed of the compressor exceeded 340 Orpm (step ■), and the defrosting thermostat was activated (step ■). enter.

Next, determine the range of rotation speed of the compressor that does not reach the limit of removal operation.
Figure 2 explains how to change the settings according to changes in outside air temperature with reference to Figure 2.3. In Figure 2, the horizontal axis represents the outside air temperature, and the vertical axis represents the sum of the outdoor heat exchanger quantities. , each rotation speed of the compressor is shown by a diagonal solid line.

The variable capacity air conditioner has a heating capacity of 11g based on changes in outside temperature.
The rotational speed of the compressor changes in accordance with changes in force, and generally, when the outside air temperature becomes low, the rotational speed of the compressor increases to ensure the heating capacity exceeds a certain value VC. Therefore, the change in outside air temperature V
By varying and setting the rotation speed of the compressor that accommodates one main shaft in accordance with this, efficient main shaft operation can be achieved.

In Figure 2, for example, as shown by the arrow, the outside temperature is 11.
When the outside temperature is 0°C, the compressor rotation speed is approximately 390Qrpm, and when the outside temperature is 0°C, the compressor rotational speed is approximately 340Qrpm.
The VC control circuit is set to enter the original shaft operation when the rpm is higher than that.

In FIG. 3, the horizontal axis represents the outside air temperature, the vertical axis represents the compressor rotation speed sound, and the thick actual machine 1 shows the line during stable operation when there is no damage to the outdoor heat exchanger. Furthermore, the inside of the hub teng indicates the rotational speed range in which the load removing operation should be started.

FIG. 3V Therefore, similarly to FIG. 2, it is possible to set the number of revolutions at which the original shaft operation should be started in accordance with changes in the outside temperature.

The example in Figure 3 is an example where the absolute humidity of the outside air is low and the amount of adhesive is small.In the low temperature range below -5°C, the set rotation speed of the compressor is set high, and the setting in Figure 2 is used. The original axis effect 4 is better than that of
Kura improvement +! ” can be done.

According to the embodiment described above, in a variable capacity air conditioner, if the outdoor heat exchanger is not suitable for use or the amount of modification is small, it can be controlled so as not to enter the main shaft operation. This has the effect of preventing energy consumption due to operation and a drop in temperature inside the mold.

In addition, the numerical value of the compressor rotation speed and the outside air temperature value: 4 in the above example are - examples, and depending on the VC such as the capacity of the compressor, the model, the conditions of the environment in which the air conditioner is used, etc. Needless to say, appropriate setting values should be set for each.

〔Effect of the invention〕

As described above, according to the present invention, the spindle is operated only when the spindle is really needed, thereby preventing energy consumption and a drop in indoor temperature due to unnecessary spindle operation. It is possible to provide a control method for controlling a variable capacity air conditioner.

[Brief explanation of the drawing]

FIG. 1 is a flowchart of both methods for removing and controlling four variable-capacity air conditioners according to an embodiment of the VC of the present invention, and FIG. FIG. 3 is a diagram showing the relationship between the outside air temperature and the rotation speed of the compressor. 1...Line during stable operation. Nth Ntra [l furi, r hair (l nino hai 3riU I #! 11 movement ^f group

Claims (1)

[Claims] 1. Ability to perform capacity control by changing the rotation speed of the compressor motor.During heating operation in a variable air conditioner, the rotation speed of the compressor motor is measured, and the rotation speed of the compressor motor is measured. Defrosting operation does not start when the rotation speed is lower than a preset rotation speed, and the rotation speed range in which defrosting operation does not start is set by changing it according to changes in outside air temperature. A defrosting control method for a variable capacity air conditioner, characterized by controlling the air conditioner so as not to enter defrosting operation. 2. In the method described in claim 1, the defrosting operation is started only when the rotation speed of the compressor motor exceeds a preset rotation speed and the defrosting thermostat is activated. A defrosting control method for a variable capacity air conditioner.